Lymphatic System

Question 1

Role of lymphatic system in non specific defence

Answer 1

Lymph enters lymph nodes and any debris, worn out cells, micro-organism, bacteria gets stuck on mesh work of fibres in nodes
Macrophages ingest particles
When an infection occurs, number of lymphocytes increase and lymph node becomes swollen and sore

Question 2

Lymph vessel

Answer 2

One way system
Carries lymph
Blind ended
More permeable
Larger than blood vessels
Valves
In between tissue fluid

Question 3

Lymph node

Answer 3

AKA lymph gland
Occur at intervals along lymphatic system
Bean shaped
Lymphoid tissue- containing macrophages and lymphocyte
Mesh work of lymph node fibres- foreign particle sticks here

Question 4

Phagocytosis

Answer 4

Process by which a cell surrounds and takes in solid particles
Engulf and digest micro organisms and cell debris
Leucocytes (secrete substance before engulfing) and macrophage (large + powerful)

Question 5

Pathogen

Answer 5

Disease- causing organisms

Bacteria (single called organism), virus (infectious agent), fungi, animal parasite

Question 6

Contagious

Answer 6

Passed by direct contact

Question 7

Vector

Answer 7

Intermediate hosts of pathogens

Eg. Mosquito

Question 8

Role of lymphatic system

Answer 8

Collect escaped fluid from capillaries and return it to circulatory system (drainage)
Body’s internal defence against pathogenic organisms